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Consonant doubling

There are four consonants in native Japanese words, /p/, /t/, /k/, and /s/, that can get doubled. In this case they take up an extra mora, but the general effect is to insert a pause that sounds as long as a regular syllable with a short vowel.

For example:

juppun - ten minutes
chotto - a little bit
gakkoo - school
kissaten - tea house


In the Japanese pronunciation of foreign loan words, the voiced consonants /b/, /d/, /g/, and /z/ can also be doubled.

For example:

gubbai - goodbye
guddo - good
doggu - dog
kizzu - kids


Don't say the consonant twice, just make the middle a bit longer. To get an idea, think of "map page", "hot taco", "sick kid", "nice seafood", etc.

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Long Vowels

When a vowel occurs twice in a row, it becomes a "long vowel," with the second one being a full mora. Here is how these long vowels will be written:

aa, ii, uu, ee, oo

(In Hebon-shiki, it would be written ā, ī, ū, ē, ō).

Alternatively, you will also see "ei" and "ou". Unless the "e" and the "i" (or the "o" and the "u") are split between two words, these are pronounced the same as ē ō.

For example, arigatou is pronounced as if it's spelled arigatō, while sensei is pronounced as if it's spelled sensē. arigatou　 a-ri-ga-to-o Thank you sensei　　 se-n-se-e Teacher